A large body of new and significant data on the mechanisms regulation of anion (and proton) transport has accumulated rapidly during the past decade. These have been obtained from epithelial cells (renal, gastric, intestinal, salivary, pancreatic, and ocular tissues) in non-epithelial cells (erythrocyte, axone, muscle, Ehrlich tumor cells, and bacterial cells) and subcellular organelles (mitochondria, membranes fragments or vesicles); and are concerned with the following: (1) The discovery of some heretofore unrecognized anion transport processes; (2) The development of newer techniques including : NMR spectroscopy, electron magnetic resonance, micro pCO2 electrodes picapnometer for total CO2 content; microglass electrodes for H, Na, K; and the micro-chloride electrode. (3) The isolation of anion or proton transport-related enzymes (K.ATPase, membrane-bound carbonic anhydrase, disulfonic stilbene binding proteins, norepinephrine-sensitive adenylate cyclase and others) and their reconstitution into synthetic membranes with restoration of the transport process; (4) The regulation of various anion transport processes by adrenergic and cholinergic neurotransmitters, peptide and steroid hormones and calcium. (5) The development and use of new pharmacodynamic agents including: disulfonic stilbenes, guanidino compounds, histamine and its H-1 and H-2 antagonists, and others. The overall purpose of this proposed conference is to simulate the exchange of information on the fundamental concepts of anion transport. This has become necessary because a clear understanding of the rapid progress in this field has often been frustrated by the different approaches and definitions used by physiologists, biochemists, pharmacologists, microbiologists, and clinicians who are producing new and challenging data on anion transport processes in a wide variety of cellular and sub-cellular systems. It is expected that such a conference of the participating investigators, together with publication of its proceedings in the Annals of the N.Y. Academy of Sciences, will integrate fundamental principles, disseminate new information, and thereby promote new research in several scientific disciplines.